Winch



J. H. WILSON Aug. 7, 1951 WINCH 5 Sheets-Sheet 1 Filed June '7, 1946 John Han, Mlsoh INVENTOR.

BY wm gou,hwa;wwam

1951 J. H. WILSON 2,563,089

WINCH Filed June 7, 1946 5 Sheets-Sheet 2 Aug. 7, 1951 J. H. WILSON 2,563,089

WINCH Filed June '7. 1946 5 Sheets-Sheet 5 INVEN TOR.

I omaw,co ,w+w@m Patented Aug. 7, 1951 UNITED STATES PATENT OFFICE WINCH John Hart Wilson, Wichita Falls, Tex. Application June 7, 1946, Serial No. 675,220

This invention relates to rotary well drilling rigs and the like, and more particularly to the hydraulic braking installation associated with the hoisting mechanism.

In earlydrilling equipment, whether in connection with the bull wheel, the calf wheel, or the sand reel or draw-Works drums, the retarding or checking of the fall of loads into the well was effectedonlyby mechanical friction brakes, usually of the band brake type, under the control of the operator. Such brakes were subject to rapid failure due to excessive wear, and in these days of deeper wells and heavier equipment, they are seldom-employed alone in lowering drill pipes and the like into the wells.

To meet the need for an efiective means for relieving the brakes of such wear and liability of breakage due to the great weights handled in drilling a deep well, and of the damage caused by the high speeds of operation, there was developed the hydraulic fluid brake which, when coupled to the drum-shaft, serves to retard the free fall of the string of drill pipe, or other loads, and to absorb the great amount of energy developed.

In drilling a well, it becomes necessary at times to pull the string of drill pipe--as for example when the drill bit must be renewed or repaired-- and then to replace the drill pipe in the bore hole. The lowering or replacement of the string of pipe is referred to as going in the hole and the raising and removal of the ipe is called coming out of the hole.

The operation of going in the hole consists of the alternate lowering of the string of pipe the distance equal to the length of the newly coupled stand of pipe, and lifting the empty travelling block to attach another stand to the string. Obviously, the necessity of braking or retarding the descent of the load by other means than the usual winch controlling band brake arises only when the drill pipe is being lowered, and it is desirable that some means be provided for disconnecting the supplemental braking or retarding device when the cable is being wound on the drum in raising the block. Otherwise,

4 Claims. (01. 254187) unnecessary power would be expended in working against the extra load imposed by such retarding means.

When coming out of the hole, the winch drum is alternately driven to wind the cable to raise the string of pipe in order to detach the succes sive stands, and then allowed to run free while the cable is unwound to permit the empty block to descend tobe:c'onnected again with the drill pipe; It wiiipe readily understood that ring" neither of these operations inVOlVed in coming out of the hole, is there any necessity nor d'esirability for the use (if supplemental braking or retarding means. When the pipe is being raised, the imposition of the additional resistance Of a brake would be a foolish waste of power; and

during the alternate operation of lowering the travelling block, the weight of the empty block ordinarily would not be enough to rotate the winch drum to unwind the cable if the drum were retarded by any braking means, and power would have to be applied to run the drum in the reverse direction.

It is therefore an object of the present inven tion to provide a novel and improved hoisting system particularly adapted to use in connection with the drilling of oil wells, in which a hydraulic retarder or brake is coupled to the winding drum or winch, by means of both a manually operated clutch and a one-way or overrunnin'g clutch,

whereby the brake meehanism may be automatically released when the drum is rotated to raise the load and may be manually connected and disconnected at will when it is desired that the drum rotate freely in the unwinding direction. i In the preferred embodiment, the manual clutch 'of the jaw clutch typeand the overrunning clutch are operatively disposed in series, with the manual clutch nearer to the drum or other hoisting' means.

Applied specifically to the well drilling operation the functioning of the clutches or couplings is as follows:

A. Going in the hole (1) Lowering the pipe Manual clutch eng'ag'ed Overrunning clutch automatically,

engaged (2) Raising empty block Manual clutch engaged Overrunning clutch automatically disengaged 3. Coming out of the hole (1) Raising the pipe Manual clutch disengaged Overrunning clutch thus discon nected- (2) Lowering empty bloc Manual clutch disengaged Overrunning clutch thus disconnected the two clutches is used alone. The use of an overrunning clutch only would not permit the accomplishing of operation B (2) without the application of power to drive the drum in the reverse direction, and the use of a manually operated jaw clutch alone is subject to serious objections and positive dangers.

First, it will be realized that in lowering the string of pipe stand by stand, the operator would have to engage the jaw clutch each time a stand of pipe is lowered and disengage the clutch whenever the block is raised to connect with the next stand of pi e. Since there may be as many as one hundred and fifty or more stands of pipe to be lowered into a deep well, it will be seen that approximately three hundred operations would be required in engaging and disengaging the jaw clutch in accomplishing this purpose.

Then again, in case of the use of a jaw clutch alone, if the operator should fail to disengage the clutch when the hoisting machinery is driven to raise the tackle, there would be an unnecessary waste of power in driving the hoist against the inertia of the brake. The most serious objection of all, however, to the sole use of the manually operated jaw clutch lies in the frequent failure of the driller, through negligence or accident, to engage the jaw clutch at the proper time before the lowering is commenced, and then when he attempts to engage the clutch while the hoist drum is paying out the cabl at a high speed and the hydraulic brake is idle, serious breakage and consequent loss of drilling time ensues. The rotating drum weighs several thousand pounds and the motor of the hydraulic braking mechanism may weigh, or oifer a resistance of, from 1500 to 2000 pounds. The shock caused by the engagement of the jaw clutch under these conditions is so great that it is not unusual for the drum shaft key to be sheared, or other serious damage caused to the braking system or other parts of the drilling rig.

Other objects and features of novelty, including certain details of construction of the brake system, will be apparent from the following specification when read in connection with the accompanying drawings in which one embodiment of the invention is illustrated by way of example.

In the drawings,

Figure 1 is a fragmentary view of a rotary drilling rig, showing the hoisting mechanism and the braking system in elevation;

Figure 2 is a view in elevation, and on an enlarged scale, of the hoisting mechanism and the brake system;

Figure 3 is a vertical sectional view through the aligned drum and brake shafts, showing the couplings and clutches in considerable detail;

Figure 4 is a transverse sectional view through the one-way clutch, taken on line 4--4 of Figure 3;

Figure 5 is a transverse sectional view through a portion of the shaft coupling as taken on line 55 of Figure 3; and

Figure 6 is a transverse sectional view through the jaw clutch and taken on line 6-5 of Figure 3.

Referring more particularly to Figure 1 of the drawings, it will be seen that the conventional derrick for the rotary drilling rig is indicated at W, and is provided with a base i I upon which the skid I2 of the hoisting assembly is adapted to rest. Spaced pedestals or hearing supports I4 are carried by the skid l2 and. these in turn provide sturdy and rigid mountings for the bearings l5 the shaft i6 is of conventional type and is driven through the sprocket and chain transmissions, indicated at it and I3, from suitable sources of power (not shown).

The cable 20 is wound upon the drum and passes over the crown block sheaves 21 at the top of the derrick l0, and supports a travelling block 22 from which is suspended a swivel 23, which serves to support the upper end of a string of drill pipe 24. As thus far described, the parts of the rig are conventional.

The end of the hoist drum shaft I6 which extends toward the left in Figures 1, 2, and 3 of the drawings, is provided with splines as at 25 whereby it is keyed to the axially movable element 25 of the jaw clutch 27. This movable element 26 is adapted to be engaged with the complementary element 28 of the jaw clutch by means of the hand lever 29, the lower end of which is pivoted as at 30 to a projection 31 on the pedestal l4.

As shown most clearly in Figure 3 of the drawings, driven element .28 of the jaw clutch assembly 21 is mounted on an extension 32 of the drum shaft [6 and is relatively rotatable with respect to said shaft by virtue of the ball bearings 33, this bearing assembly being covered by the cap or plate 34 bolted to the jaw member 28.

The element 28 of the jaw clutch 21 is provided at its left hand edge with a sprocket portion 35 which mates with a similarly formed sprocket 36 formed on an intermediate coupling member 31. An endless sprocket chain 40 surrounds these two adjacent sprocket elements. At the left hand edge of the intermediate coupling element 37 there is formed another sprocket wheel 4 l, which is connected by means f an endless chain 42 with the sprocket 43 formed on the annular hub member 45. This latter member 45 is secured to the outer clutch member 46 of the one-way clutch device 41, by means of the bolts 48. The inner hub member Ell of the one-way clutch 41 is keyed as at 52 to the shaft 53 which extends into the hydraulic brake or retarding device 55 and is secured to the rotary element thereof.

The flexible self-alignin coupling 28, 31, 45 inclusive is preferably enclosed in a housing 10 which may conveniently be formed in two sections H and 12 as clearly indicated in Figures 3 and 5 of the drawings. The sections H and 72 are preferably flanged as at 13 and recessed as at 14 so that the securing bolts 15 may be readily applied. Th end flanges 16 of the housing 10 may be provided with seals T! where they fit cylindrical portions of the elements 28 and 45.

Referring now to the details of construction of the oneway clutch 4'1, the outer member 46 of this device is mounted for rotary movement with relation to the inner hub element by means of the pair of ball bearings 55, one arranged upon either side of the central portion of the clutch. A plate 58 secured by the bolts 51 is provided at the side of the outer member 46 opposite to the one to which the member 45 is secured, and the oil seal rings 59 and 60 seal off the elements 58 and 45 respectively with respect to hub portions formed on the inner clutch member 50. By this means lubricant may be retained within the clutch.

The principal operative portions of the clutch are best seen in Figures 3 and 4 of the drawings and they comprise the rollers 62 which are received within the cylindrical bore of the outer member 46 and the inclined cams 63 of the inner member 50. A cage 64 serves to retain the rollers in spaced relation around the periphery of the clutch. Thecage 64 is permitted limited movean ear 66 secured to the cage 64, and the other ends of the springs are secured to hook elements 6! carried by the inner member 56. The tension of the springs '65 serves to urge therollers 52 up the inclines of the cam portions 63 and thus when the outer or driving element 46 of the clutch is rotating in the direction of the arrow A the rollers 62 will be urged up the inclines 63 into wedging engagement between the outer driving'element 46 and the inner driven element 50, and the brake shaft 53 will be rotated within the hydraulic brake chamber and the retarding effect will be attained.

Upon reversal of the direction of rotation of the outer driving element 46 of the clutch, however, the rollers 62 will be moved down the in.- clined cam faces 63, against the urging. of the springs 65, and the outer member will rotate while the inner element remains stationary.

Obviously, with the jaw clutch engaged, the

overrunning clutch will be in engagement when the drum H is rotating in a direction to unwind the cable 20, but the overrunning clutch will be rotated freely without engagement of the brake when the drum I1 is being driven in a direction to wind up the cable and raise the empty block. In this way the viscous hydraulic fluid in the brake will absorb the greater part of the energy of free fall of the load into the well and will cause a controlled and even descent of the drill stem without destructive wear on the braking and clutching parts. The final stopping of the descent of the load when a stand of pipe is lowered is effected by the usual manually controlled brakes, certain bands of which are indicated at I1 in Figures 1 and 2.

Of course, when the string is being raised from the well, the jaw clutch will be disengaged, thus disconnecting the hydraulic brake and the oneway or overrunning clutch from the drum shaft completely. In this way, the hoisting machinery will be relieved of wear and tear and the useless dissipation of power which would be necessary to wind the cable against the resistance of the hydraulic braking mechanism, and also the empty travelling block will descend by its own weight.

Various changes and modifications may be made in the embodiment illustrated and described herein without departing from the scope of the invention as defined by the following claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a well drilling rig of the class described, in combination, a supporting base, a hoist drum, a drum shaft upon which said drum is fixed, bearings on said supporting base for said drum shaft, a retarding braking mechanism for said shaft also mounted on said supporting base, a rotor forming a part of said braking mechanism, a brake shaft upon which said rotor is fixed, said brake shaft being in axial alignment with said drum shaft, a jaw clutch carried by said drum shaft, one element thereof being rotatable on the end of said shaft and the mating element splined on said drum shaft for rotation therewith, and manual means for engaging and disengaging said jaw elements, an automatic one-way driving coupling carried upon said brake shaft, an inner member thereof being fixed on said brake shaft and provided with a peripheral series of inclined cam surfaces, an outer substantially annular member of said coupling which is concentric with said inner member and provided with a smooth' cylindrical bore, and a circular series of spaced rollers disposed between said members, one rolle'r' being allotted to each of said cam surfaces, and

means connecting said outer coupling member with the first named jaw clutch element on the drum shaft.

In a rotary drilling rig for raising and lowering drill pipe and the like in the bore hole of a well, in combination, a hoisting cable, a holstdrum, means for driving said drum in the direction to wind the cable on the drum, a drum shaft 3 on which the drum is fixed, a retarding brake mechanism adjacent said drum, said brake mechanism including a brake shaft and a rotor fixed to envelop and receive a respective end of one of said shafts, a rotary bearing operatively disposed between the periphery of the end portion of the drum shaft and the hollow end of the coupling device which receives'it, a jaw clutch' element rigid with said hollow end, a sliding jaw clutch element splined on the drum shaft, and manual means for moving said last named clutch element into and out of engagement with said first named jaw clutch element, a one-way overrunning clutch means operatively disposed between the periphery of the brake shaft end portion and the hollow end of the coupling device surrounding it; whereby an operator may completely disconnect the brake shaft from the drum shaft for rotation of the latter free of the retarding brake mechanism in both directions, or connect the two shafts through the positive clutch means while the one-way automatic clutch connects the shafts so that the drum must drive the brake when rotating in one direction but will rotate free and unimpeded by the brake in the opposite direction.

3. In a rotary drilling rig for raising and lowering drill pipe and the like in the bore hole of a well, in combination, a hoisting cable, a hoist drum, means for driving said drum in the direction to wind the cable on the drum, a drum shaft on which the drum is fixed, a retarding brake mechanism adjacent said drum, said brake mechanism including a brake shaft and a rotor fixed upon said brake shaft, means supporting said shafts for rotation in substantial axial alignment with projecting end portions of said shafts directed toward each other but spaced apart, and a coupling device adapted to effect flexible and disengageable driving connections between said shafts; said device having hollow cupped ends each adapted to envelop and receive a respective end of one of said shafts, said device being axially immovable with respect to said shafts, an antifriction bearing operatively disposed between the periphery of the end portion of the drum shaft and the hollow end of the coupling device which receives it, a jaw clutch element rigid with said hollow end, a sliding jaw clutch element splined on the drum shaft, and manual means for moving said last named clutch element into and out of engagement with said first named jaw clutch element, a one-way overrunning clutch means operatively disposed between the periphery of the brake shaft end portion and the hollow end of the coupling device surrounding it; whereby an operator may completely disconnect the brake shaft from the drum shaft for rotation of the latter free of the retarding brake mechanism in both directions, or connect the two shafts through the positive clutch means while the one-way automatic clutch connects the shafts so that the drum must drive the brake when rotating in one direction but will rotate free and unimpeded by the brake in the opposite direction; the intermediate portion of said coupling device being provided with a flexible joint whereby minor fortuitous misalignments of the two shafts may be accommodated.

4-. In a Well drilling rig of the class described, in combination, a supporting base, a hoist drum, a drum shaft upon which said drum is fixed, bearings on said supporting base for said drum shaft, a retarding braking mechanism for said shaft also mounted on said supporting base, a rotor forming a part of said braking mechanism, a brake shaft upon which said rotor is fixed, said brake shaft being in axial alignment with said drum shaft, a jaw clutch carried by said drum shaft, one element thereof being rotatable on the end of said shaft and the mating element keyed on said drum shaft for rotation therewith, and manual means for engaging and disengaging said jaw elements, an automatic one-way driving coupling carried by said brake shaft, an inner 8 substantially annular member of said coupling being fixed on said brake shaft and provided with an outer surface, an outer substantially annular member of said coupling which is concentric with said inner member and provided with an inner surface surrounding and spaced peripherally from the outer surface of the inner annular member, and at least one look element disposed between said surfaces, the surfaces of said members and of said last-named element being so constructed and arranged that the said coupling members are locked in driving relationship upon rotation of the coupling in one direction, and means connecting said outer coupling member with the first named jaw clutch element on the drum shaft.

JOHN HART WILSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,708,215 Chryst Apr. 9, 1929 1,965,145 Klaucke July 3, 1934 1,992,912 De La Mater Feb. 26, 1935 2,271,252 Cardwell et al J an, 27, 1942 2,282,616 Spalding May 12, 1942 

